This invention relates to diaphragm valves for use in controlling the flow of fluids consisting of or containing aggressive media, and which are particularly useful in steam environments, e.g., dishwashers, laundries, and sterilizers. More specifically, the invention is directed to a modular valve diaphragm and valve seat cartridge which resists wear in a steam environment, and which can be readily and inexpensively replaced.
It is know in the art to employ a diaphragm valve wherein a diaphragm is moved by the armature of a solenoid for opening and sealing an orifice in the main seat of the valve. In order to maintain light weight and flexibility, it is desirable to have valve diaphragms that are relatively thin. However, the life of a diaphragm decreases as it is made thinner due to increased fragility and a tendency to extrude when placed under pressure, as when the diaphragm is urged against the valve seat. Moreover, due to the aggressiveness of the fluid, the flow of which is being controlled by the valve, the pilot seat and main valve seat are subject to accelerated wear and corrosion which can require the time consuming and expensive remedy of replacing the entire valve assembly.